Lumber cart having cradle with variable height

ABSTRACT

A lumber cart for use in the lumber industry such as a sawmill for receiving lumber pieces one at a time from a conveyor such as a lumber sorter, which categorizes lumber into categories having identical dimensions. The cart includes a rectangular frame supported on four wheels adapted to ride on rails, four stanchions positioned one at each corner and a winchlike mechanism having two spools for winding wire rope cable onto and a brake band and drum portion which creates holding action of the spools stopping rotation of the spool assembly when the brake band is allowed to engage the brake drum. The wire rope cable is arranged between the two forward stanchions and the two rearward stanchions in such a manner that the slack in the suspended cable forms a cradle for receiving the lumber pieces at an elevation near the uppermost portion of the stanchions and the winchlike mechanism enables the cradling portion of the cables to slippingly change elevation downwardly to variable heights. Two of the stanchions, one fore and one aft both being on the same side of the cart, are pivotally attached to the frame allowing them to articulate outwardly facilitating unloading.

United States Patent Primary ExaminerAlbert J. Makay Attorney-John R.Walker, Ill

ABSTRACT: A lumber cart for use in the lumber industry such as a sawmillfor receiving lumber pieces one at a time from a conveyor such as alumber sorter, which categorizes lumber into categories having identicaldimensions. The cart includes a rectangular frame supported on fourwheels adapted to ride on rails, four stanchions positioned one at eachcomer and a winchlike mechanism having two spools for winding wire ropecable onto and a brake band and drum portion which creates holdingaction of the spools stopping rotation of the spool assembly when thebrake band is allowed to engage the brake drum. The wire rope cable isarranged between the two forward stanchions and the two rearwardstanchions in such a manner that the slack in the suspended cable formsa cradle for receiving the lumber pieces at an elevation near theuppennost portion of the stanchions and the winchlike mechanism enablesthe cradling portion of the cables to slippingly change elevationdownwardly to variable heights. Two of the stanchions, one fore and oneaft both being on the same side of the cart, are pivotally attached tothe frame allowing them to articulate outwardly facilitating unloading.

Patented May 11, 1971 v 2 sheets -sheet 1 INVENTOR EDWARD M. HARVEYBACKGROUND OF THE INVENTION l. Field of the Invention This inventionrelates to lumber carts for use in the lumber industry, as in a sawmill.

2. Description of the Prior Art The typical prior art lumber carts usedwith a lumber sorter included a four wheel cart with upstandingstanchions to contain the lumber dropped from the lumber sorter to thebottom of the cart during the initial loading thereof-In other words,the cart was loaded from adjacent the bottom progressively upwardly. Inaddition, in some of the prior carts the stanchions of the carts werepivotable so that they would pivot downwardly in unloading.

There were certain disadvantages to the prior carts, among them beingthe following: There was a tendency for the lumber to break or splitduring loading, particularly the first pieces loaded in the cart sincethere was a considerable distance that the pieces had to fall from thelumber sorter to the bottom of the cart. Also, the lumber had a tendencyto bounce after falling such a distance and, therefore, the pieces oflumber were not always positioned in relatively parallel relationshipwith one another.

SUMMARY OF THE PRESENT INVENTION The present invention is directedtowards providing an improved lumber cart and one which overcomes theheretofore mentioned and other disadvantages of prior lumber carts.

One of the principal concepts of the present invention is to provide anadjustable cradle means which enables the lumber pieces to be receivedrelatively close to the disengagement mechanism of the lumber sorterwhether it be the first piece to fall on the cart or the last Saidcradle means is provided by pair of flexible elongated members such aswire rope cables or the like which are each anchored at one of the endsthereof and extend through pulleys and span the distance between theforward and rearward pairs, respectively, of the stanchions. Theelongated members are led downwardly and to spools on a spool and brakeassembly. The spool and brake assembly is actuated by a crank to raisethe cradles upwardly to an initial loading position, and means isprovided for manually releasing the brake at desired times to allow theweight of the lumber to carry the cradles downwardly at intervals as thelumber is being loaded so that the falling distance of the lumber piecescan be kept at a minimum throughout the loading process.

Another feature of the present invention is the provision of eliminatingbinding of the lumber between stanchions during unloading by a forklifttruck. Thus, two of the stanchions are pivotable and have inwardlyextending shoes adjacent the lower ends thereof. During the initialphases of the loading, the weight of the lumber keeps the pivotablestanchions in an upright position and towards the latter part of theloading, the weight of the pieces rest on the shoes and keep thestanchions in a positive vertical position. Then, during the liftingaction of the forklift, which displaces the weight of the lumber piecesfrom the shoes and the cradle, the pivotally attached stanchions areallowed to articulate outwardly nullifying any lateral binding betweenthe stanchions.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view ofthe lumber cart of the present invention.

FIG. 2 is a rear elevational view thereof, and showing in broken lines apivotable stanchion in tilted position.

FIG. 3 is a sectional view taken as one the line III-III of FIG. 1.

FIG. 4 is a sectional view taken as on line IV-IV of FIG. I.

FIG. 5 is a somewhat diagrammatic view showing the loading of the lumbercart from a lumber sorter during the initial phases of the loading.

FIG. 6 is a view of the same after the can has been loaded.

FIG. 7 is a view of the same during unloading thereof by a forklifttruck, with the forklift truck being shown in broken lines.

DESCRIPTION OF PREFERRED EMBODIMENT The lumber cart of the presentinvention indicated by numeral 11 is intended for use in thelumber'industry, more particularly as in a sawmill. Cart 11 is one of aplurality which are positioned side by side forming a straight lineunder a conveyor such as a lumber sorter 13 which moves transverselyoverhead at a substantial height and automatically or remotely selectsor sorts lumber pieces 15 as to length or width, etc., by disengaging,and thus allowing to fall, all like piece 15 one at a time onto one suchcart 11. Cart 11 includes a rectangular shaped frame 17, which is madefrom two opposing channel iron longitudinal members 18, 18 or the likein spaced apart relationship on the one side and two opposing channeliron longitudinal members 19, 19' or the like in spaced apartrelationship on the other side, a forward I-beam lateral member 21 and arearward I-beam lateral member 21. Frame 17 is supported by at leastfour wheels 23 rotatably mounted fore and aft between longitudinalmembers 18, 18 and 19, 19 respectively on axles 23, wheels 23 being freeto runningly ride on rails 25.

Two stanchions, one forward and one rearward 27, 29 respectively, formedfrom I-beam steel or the like are fixedly attached in a verticalposition adjacent the comers of one side of the horizontal frame.Sloping members 28 are respectively fixedly attached at the oppositeends thereof between stanchions 27, 29 and frame 17. The forwai'dstanchion 27 is fixedly attached adjacent the junction of longitudinalmember 18, 18 and lateral member 21'. The rearward stanchion 29 isfixedly attached adjacent the function of longitudinal members 18, 18'andlateral member 21'. Two stanchions, one forward and one rearward 30,31 respectively formed from I- beam steel or the like include crossmembers or shoes 37, 39 respectively fixedly attached at the lower endsthereof, with each of stanchions 30, 31 now having the shape of an L.Stanchions 30, 31 are pivotally attached in a vertical position adjacentthe corners of the other side of horizontal frame 17 from stanchions 27,29 so that the four stanchions 27, 29, 30 and 31 are disposed at thefour comers of frame 17. Forward stanchion 30 is pivotally attachedadjacent the junction of Iongitudinal members 19, 19 and lateral member21 of frame 17 and rearward stanchion 31 is pivotally attached adjacentthe junction of longitudinal members 19, 19' and lateral member 21 offrame 17. Forward stanchion 30 pivots around pivot pin 33 and rearwardstanchion 31 pivots around pivot pin 35. Both stanchions 30, 31 havehorizontal members or shoes 37, 39 directed inwardly.

FIG. 2 shows stanchion 31 in solid lines in a vertical position and inbroken lines in a tilted position. It will be noted that when stanchion31 is in a vertical position, shoe 39 is in a substantially horizontalposition, and when stanchion 31 is tilted downwardly, shoe 39 iscorrespondingly tilted upwardly.

It should be understood that shoe 37 and shoe 39 are fixedly attached tostanchions 30, 31 respectively at an angle which insures that stanchions30, 31 are in the vertical position when shoes 37 and 39 are resting onlateral cross members 21, 21 respectively.

Sloping members 40 are respectively fixedly attached adjacent the upperends thereof to stanchions 30, 31 and angled downwardly where they arefixedly attached at the lower end thereof to the respective shoes 37,39,. In order to provide a better understanding of the structure ofshoes 37, 39 and since both shoes and stanchions 30, 31 are identical, amore detailed description of rearward shoe 39, rearward stanchion 31 andtheir attachment to frame 17 will now be discussed.

Referring now to FIGS. 1, 2 and 4, stanchion 31 is formed from I-beam,steel or the like. Shoe 39 is constructed of a pair of verticallydisposed parallel platelike members 41 and.a horizontal platelike member43 fixedly attached along the 'slippingly engages a portion upper edgesof platelike members 41 and at butt edge to the inward face of stanchion31. Members 41 extend outwardly beyond stanchion 31 to provide theoutward portions 39" of platelike members 41 which have apertures forreceiving pivot pin 35.-Pin 35 is horizontally received throughapertures in a pair of vertically disposed parallel cars 45 which arefixedly attached to the outermost end of lateral frame member 21 Twoelongated flexible members as wire rope cables or the like, one rearwardand one forward 51, 53 respectively, will now be discussed (refer toFIGS. 1 and 2). One end of cable 51 is anchored with a wire rope thimbleand clamp 55, 57 respectively adjacent the upper portion 31 of stanchion31. Cable 51 then extends upwardly and over a fixedly attached pulley orsheave 59 positioned at the uppermost extremity of stanchion 31, thenextends laterally to a pulley 61 attached to the upper end 29' ofstanchion 29 with the rotating axis parallel to longitudinal axis ofcart 11, thence downwardly adjacent and parallel to stanchion 29 to apulley 63 attached to lateral member 21', with the rotating axis beingparallel to the lateral axis of cart 11, thence forward horizontally andparallel with the longitudinal axis of cart 11 to and finallyterminating at a spool 75, which will be described further on. Cable 53is anchored at one end in like manner as described for cable 51 adjacentupper end 30' of stanchion 30. Cable 53 extends up wardly to a fixedsheave 65, thence laterally to pulley 67 axially attached to the upperend 27 of stanchion 27, the rotating axis being parallel to thelongitudinal axis of cart 11, thence downwardly adjacent and parallel tostanchion 27 terminating at a spool 77, to be described further on. Theslack in the suspended wire rope cable 51 between stanchions 29, 31forms a rearward arcuate cradle 69, as best viewed in FIG. 5.

' The slack in the suspended wire rope cable 53 between stanchion 27, 30forms a forward arcuate cradle 71. It should be understood that cradles69, 71 are preferably parallel one with the other, therefore, FIGS. -7depict cradle 69 only which theoretically obliterates viewing cradle 71.Cradles 69, 71 have the function of receiving a plurality of lumberpieces as they fall from the lumber sorter 13. The height of thereceiving cradle 69, 71 is variable by a winchlike dual spool and brakeassembly 73, which will now be described.

Brake assembly 73 comprises takeup spool 75 for cable 51, takeup spool77 for cable 53, a brake drum 79, a brake band 81 and a crank 83 to windthe takeup spools. The two spools 75, 77 and brake drum 79 are gangedtogether on shaft 85 which is axially attached through a pair ofbearings 87, 89 to a support bracket 91. Brake assembly 73 isinterconnected by support bracket 91 to lateral frame member 21 adjacentstanchion 27 outboard of the periphery of frame 17 (see FIGS. 1 and 3).A brake handle 93 having an amt forming a bell crank lever 95 ispivotally attached through interconnecting support structure 97 at pivotpin 99, to stanchion 27. A pull spring 101 having one end swingablyattached to stanchion 27 and the other end swingably attached in anaperture 103 in upper portion 93' of brake handle 93 urges brake handle93 inwardly toward stanchion 27 (see FIG. 1). Brake band 81 has a fixedend 81' and a movable or actuating end 81". Fixed end 81' is fixedlyattached to support structure 97 and band 81 of the circumference ofbrake drum 79. Actuating end 81" clampingly binds brake band 81 aroundbrake drum 79 indirectly by the inward pull of spring 101, handle 93 isurged inwardly rotating bell crank 95 arcuately clockwise, as viewed inFIG. 1, which in turn pulls a pushrod 109 and a clevis 105 as clevis 105rotates around clevis pin 107. Pushrod 109 is preferably threaded ateach end. Clevis 105 engages threads on one end and adjusting nut 111engages threads on the opposite end. Adjusting nut I11 facilitatesadjustment of brake band 81, as best viewed in FIG. 1.

In operation, with car 11 preferably being empty, a workman operateshand crank 83 which is keyed to shaft 85, thus winding the cables 51, 53onto spools 75, 77 which in turn takes up the excessive slack in cradles69, 71 placing them at the uppermost portion of stanchions 27', 29', 30'and 31.

Cart 11 is moved to a position directly beneath lumber sorter 13, asbest viewed in FIGS. 5 and '6. As the lumber pieces 15 continue movingalong the lumber sorter 13, all pieces 15 of a predetermined size aredropped and caught in cradle 69, 71. As lumber pieces 15 commencespiling up, the workman momentarily actuates brake handle 93 by pullingoutwardly, this action relaxes brake band 81 thus loosening it ordisengaging it from brake drum 79. The lumber pieces 15 suspended abovethe ground on cables 51, 53 possess potential energy. When the holdingaction of brake assembly 73 is released, the lumber pieces tend to fallor move downwardly, the energy is changed to kinetic energy causingspools 75, 77 to rotate, paying out cables 51, 53 which sliptransversely under the loaded lumber pieces 15, decreasing the height ofcradle 69, 71 to a desired level. The workman repeats this procedure asfrequently as desired until the stack attains the desired height, orcart 11 is fully loaded. The adjustable height feature enables eachlumber piece 15 to be received relatively close to the disengagementmechanism of the lumber sorter 13 whether it be the first piece to fallon cart 11 or the last. This feature has a two-fold advantage: (I) Thelumber 15 always falling such a relatively. short distance greatlyreduces the possibility of braking to splitting; (2) It minimizes thetendency for the lumber 15 to bounce after fallingwhich assures thatlumber pieces 15 are positioned on cart 11 in a relatively parallelrelationship one with the other, as opposed to being crosswise. Theslipping action of cable 51, 53 beneath the suspended lumber pieces 15tends to roll the lumber pieces 15 which aids in aligning lumber pieces15 in a parallel relationship one with the other. The parallelrelationship of piece 15 enables each cart 11 to receive more pieces 15and results in a savings of labor required for straightening any pieces15 that fell in a crosswise position.

The prevailing problem of removing the lumber pieces 15 wedged betweenthe stanchions has been solved by the present invention in a mannerwhich will now be described. The two stanchions, one fore and one aft30, 31, respectively, having the label 51, 53 ends anchored theretoarticulate outwardly around pivot pin 33, 35. These two stanchions 30,31 are constructed identical and have the form of an L with thehorizontal segments of the L forming a shoe 37, 39 or resting surfacewhich the cradle 69, 71 of lumber pieces 15 is lowered upon, with thevertical segments of the L forming the upright or stanchion. The weightof the pieces 15 resting on the shoes 37 39 keeps the stanchions 30, 31in a positive vertical position. When the cradle 69, 71 is elevated,i.e., not resting on shoe 37, 39, the vertical position of the stanchion30, 31 is assured by the weight of the lumber pieces 15 suspended incradle 69, 71 with the moment of force from cable 51, 53 pullinginwardly on the sheaves 59, 65 at the uppermost portion 30, 31' ofstanchion 30, 31. It should be understood that unloading a typicallumber cart by use of a forklift would not be feasible due to thebinding or wedging of the lumber between upright support structure ofthe cart, and any attempt to lift lumber from such a cart would resultin lifting lumber pieces and cart in unity. Unloading cart 11 of thepresent invention is accomplished quickly and easily by positioning aforklift 113 transversely to the cart 11 with the tines 115 to theforklift 113 directly under the pieces 15. The lifting action of theforklift 113 displaces the weight from the shoes 37, 39 and/or theeradles 69, 71 thus allowing the pivotally attached stanchions 30, 31 toarticulate outwardly nullifying any lateral binding between stanchions30, 31 and 27, 29 of the pieces 15 as the forklift 113 is driven backaway from the lumber cart, as best viewed in FIG. 7.

Although the invention has been described and illustrated with respectto a preferred embodiment thereof, it is to be understood that it is notto be so limited since changes and modifications may be made thereinwhich are within the full intended scope of this invention.

lclaim:

1. A lumber cart comprising a rectangular frame having four comersincluding a forward pair and a rearward pair of comers wheel meansmovably supporting said frame; four stanchions including'a forwardpairvand a rearward pair of and upstanding from said frame; a forwardelongated flexible I member and a rearward elongated flexible member,means fixedly attaching one end of said forward elongatedmemberstanchions, adjacent the four corners of said frame to one of forwardpair of stanchions and fixedly attaching i one end of said rearelongated member toone of said rearward pair of stanchions, meansmovably suspending said forward elongated member across from said one ofsaid forward pair of stanchions to the other of said forward pair ofstanchions to establish a forward a cradle, means movably suspendingsaid rearward elongated member across from said one of said rear- .wardpair of stanchions to establish a rearward cradle adapted in conjunctionwith said forward cradle to hold pieces of lumber, and means forcontrolling the height of said forward movably guiding said forward andrearward elongated members to said spool means, and means attached tosaid spoolreward cradles relative to said stanchions, means pivotallymounting one of said forward pair of stanchions on said frame at one ofsaid forward comers to establish a forward pivotable stanchion pivotablebetween a normal vertical position and outwardly tilted unloadingpositions, said forward pivotable stanchion including an inwardlyextending shoe upon which the lumber pieces are adapted to rest, andmeans pivotally mounting one of rearward pair of stanchions on saidframe at one of said rearward comers-to establish a rearward trollingthe height of said forward and rearward cradles includes spool meansrotatably mounted on said frame, means means for winding said elongatedmembers on said spool means to hoist' said forward and rearward cradlesupwardly relative to said stanchions.

3. The lumber cart of claim 2 in which said means for controlling theheight of said forward and rearward cradles further includes releasablebrake means for releasing said spool means to allow said forward andrearward cradles to lower under the weight of the lumber pieces carriedthereby.

4. The lumber car of claim 3 in which said brake means includes a brakedrum fixedly mounted relative to said spool means for rotation therewithabout the'same axis as said spool means, a brake band encircling saidbrake drum, a brake handle pivotally mounted on one of said stanchions,and means interconnecting said brakehandle andsaid brake band for theactuation of said brake band by said brake handle.

ardly extending shoe

1. A lumber cart comprising a rectangular frame having four cornersincluding a forward pair and a rearward pair of corners, wheel meansmovably supporting said frame; four stanchions including a forward pairand a rearward pair of stanchions, disposed adjacent the four corners ofsaid frame and upstanding from said frame; a forward elongated flexiblemember and a rearward elongated flexible member, means fixedly attachingone end of said forward elongated member to one of said forward pair ofstanchions and fixedly attaching one end of said rear elongated memberto one of said rearward pair of stanchions, means movably suspendingsaid forward elongated member across from said one of said forward pairof stanchions to the other of said forward pair of stanchions toestablish a forward cradle, means movably suspending said rearwardelongated member across from said one of said rearward pair ofstanchions to establish a rearward cradle adapted in conjunction withsaid forward cradle to hold pieces of lumber, and means for controllingthe height of said forward reward cradles relative to said stanchions,means pivotally mounting one of said forward pair of stanchions on saidframe at one of said forward corners to establish a forward pivotablestanchion pivotable between a normal vertical position and outwardlytilted unloading positions, said forward pivotable stanchion includingan inwardly extending shoe upon which the lumber pieces are adapted torest, and means pivotally mounting one of said rearward pair ofstanchions on said frame at one of said rearward corners to establish arearward pivotable stanchion pivotable between a normal verticalposition and outwardly tilted unloading positions, said rearwardpivotable stanchion including an inwardly extending shoe upon which thelumber pieces are adapted to rest.
 2. The lumber cart of claim 1 inwhich said means for controlling the height of said forward and rearwardcradles includes spool means rotatably mounted on said frame, meansmovably guiding said forward and rearward elongated members to saidspool means, and means attached to said spool means for winding saidelongated members on said spool means to hoist said forward and rearwardcradles upwardly relative to said stanchions.
 3. The lumber cart ofclaim 2 in which said means for controlling the height of said forwardand rearward cradles further includes releasable brake means forreleasing said spool means to allow said forward and rearward cradles tolower under the weight of the lumber pieces carried thereby.
 4. Thelumber car of claim 3 in which said brake means includes a brake drumfixedly mounted relative to said spool means for rotation therewithabout the same axis as said spool means, a brake band encircling saidbrake drum, a brake handle pivotally mounted on one of said stanchions,and means interconnecting said brake handle and said brake band for theactuation of said brake band by said brake handle.